Blind mating guides with ground contacts

Abstract: An electrical connector assembly (1) comprises, a first electrical connector (2), electrical contacts (7) in the first electrical connector extending to a mating face (6) of the connector (2), alignment posts (12) and first ground contacts (10) along the alignment posts (12), both of which project beyond the mating face (6); and another, mating electrical connector (3) provided with post receiving cavities (11) with second ground contacts (10) in the cavities (11) engaging the first ground contacts (10) along the posts (12).

Description: The present invention relates to an electrical connector with alignment posts that project beyond a mating face of the connector to align the mating face with another, mating electrical connector. According to US-A-4,842,543, a known electrical connector comprises an insulating housing having a mating face for engaging another mating connector, electrical contacts in the housing extending toward the mating face, and posts projecting beyond the mating face. The posts serve as obstructions to protect the contacts from being damaged. The posts align the mating face with another mating electrical connector prior to connection of the mating face with the mating electrical connector. The posts provide obstructions without a ground connection to an electrical terminal in the connector. According to US-A-4,904,194, grounding pins project from an electrical connector and the pins incorporate springs that bias the grounding pins sideways against sides of sockets in another mating electrical connector. The pins establish a ground connection between the connector and the mating electrical connector without establishing a ground connection to an electrical terminal in the connector. US-A-4,998,892 discloses a connection system in which a receptacle connector is accurately guided into a mated condition with a plug connector mounted on a circuit board by a pair of guide pins projecting forwardly from the plug connector and having tapered conical front pin ends which are received in corresponding holes of the receptacle connector prior to any engagement of the mating contacts. The guide pins are conductive and become electrically engaged with socket contacts in the corresponding holes to establish grounding between the connectors. An objective of the present invention is to provide an electrical connector assembly comprising matable electrical connectors having alignment members fitted with ground contacts which extend along the alignment members and which can discharge an electrostatic charge to ground potential prior to connection of other electrical contacts of the connectors. The present invention consists in an electrical connector assembly comprising first and second matable electrical connectors having matable electrical contacts secured therein for electrical connection when the electrical connectors are mated together, and ground contacts for electrical connection when the connectors are mated together, characterized in that insulative alignment posts and cavities are provided on the matable connectors, and the ground contacts extend along the alignment posts and cavities and, when the connectors are mated together, electrically engage each other before engagement of the electrical contacts. The connector according to the invention is suitable for connecting an apparatus, such as a disk drive of a computer to a docking work station. The entire disk drive is inserted into a docking opening in the work station, which requires the first connector on the disk drive to align with the second or mating electrical connector in the docking opening. The alignment posts may be provided on the connector of the disk drive and project beyond the mating face of this connector. They align the mating face with the mating electrical connector prior to connection of the mating face with the latter connector. Upon connection of a disk drive into a docking opening, the disk drive becomes connected to activated circuits in a docking work station. Arcing due to electrostatic discharge could result when a connector on the disk drive is connected to the activated circuits. With this invention, the electrical ground contacts on the alignment posts of the first connector will incur the arcing to protect the activated circuits from electrostatic discharge. The ground contacts extend along the insulating alignment posts which project beyond the mating face of the connector on the disk drive. Prior to connecting the mating face of this connector with the mating electrical connector on the docking work station, the ground contacts on the alignment posts engage the mating electrical connector. Thus, the ground contacts become engaged with the mating electrical connector before the signal contacts become engaged with the mating electrical connector. It can be said of the invention, that the signal contacts, combined with the longer ground contacts, provide at least two levels of sequenced connections with the mating electrical connector. In other words, the ground contacts first engage the mating electrical connector, and subsequently, the signal contacts engage the mating electrical connector. Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which: FIGURE 1 is a perspective view of an electrical connector assembly comprising an electrical connector and a mating electrical connector, with ground contacts extending along guide pins of the first electrical connector, and with ground contacts along channels in the mating electrical connector; FIGURE 2 is a top view of an electrical connector with alignment posts and ground contacts extending along the posts; FIGURE 3 is a front view of another embodiment of the connector shown in Figure 1; FIGURE 4 is a top plan view of a metal blank form of a carrier strip that is unitary with the ground contacts for the connector as shown in Figure 1; and FIGURE 5 is a side view of a ground contact made from the blank form shown in Figure 3. With reference to Figure 1, an electrical connector assembly 1 comprises an electrical connector 2 and another mating electrical connector 3; each of which connectors 2, 3 comprises an insulating housing 4 having a rear face 5 and a mating face 6, and electrical contacts 7 in and extending through contact receiving cavities through the housing 4 from the rear face 5 toward and to the mating face 6. Each electrical connector 2, 3 further comprises electrical terminals 8 on rear ends 9 of the electrical contacts 7 that project from the rear face 5 for connection to a circuit board, not shown. Each connector 2, 3 further comprises, electrical ground contacts 10 extending in and through ground contact receiving cavities 11 in the housing 4. The electrical connector 2 further comprises, insulative posts 12; and the conductive ground contacts 10 extending along the posts 12. The ground contacts 10 are longer than the electrical contacts 7, and extend through the housing 4 and through the rear face 5. Electrical terminals 13 on the ground contacts 10 project from the rear face 5 of the housing 4 for connection to a circuit board, not shown. The posts 12 and the ground contacts 10 project outwardly beyond the mating face 6 to establish a ground connection of the ground contacts 10. A shroud 14 on the housing 4 encircles the contacts 7 at the mating face 6. The posts 12 and the ground contacts 10 of the connector 2 project outwardly beyond the shroud 14. The ground contacts 10 project outwardly beyond the mating face 6 to engage the mating electrical connector 3 while the posts 12 engage the mating electrical connector 3. With reference to Figure 1, the mating electrical connector 3 comprises the ground contact receiving cavities 11 providing sockets to receive the posts 12. The cavities 11 are in the form of channels on the mating electrical connector 3. The ground contacts 10 are in and along the channels, and face opposite open sides of the channels. Open ends 16 of the channels are spaced apart to correspond with the spacing between tips 17 of the posts 12. The ground contacts 10 in the channels receive and engage the ground contacts 10 along the posts 12 upon receipt of the posts 12 along the channels. The posts 12 project so as to align the mating face 6 of the connector 2 with the mating electrical connector 3 while the mating face 6 is spaced apart from the mating electrical connector 3. The posts 12 and the channels define opposite ends 18 of the respective connector 2 and the mating connector 3, for example, to reduce the widths of the connectors 2, 3 to a minimum dimension from end 18 to end 18. These features of the mating connector 3 can be applied to a mating connector, not shown, for mating connection with the connector 2 shown in Figure 2. With reference to Figure 1, alignment of the respective connectors 2, 3 end 18 to end 18 is accomplished by viewing along the posts 12 as sights to target where the posts 12 will align to assure insertion of the posts 12 into the open ends 16 of the channels. The mating connector 3 is often hidden from view inside a chassis, not shown, requiring the posts 12 to enter the chassis through an opening in the chassis. The posts 12 permit alignment of the connectors 2, 3 when the mating connector 3 is hidden from view. The posts 12 thereby facilitate blind mating connection of the connectors 2, 3. Each of the posts 12 is tapered forwardly toward the forward tip 17. Each of the posts 12 tapers inwardly along its length from the end 18 of the connector 2. A flat surface 19 on the post 12 merges with the flat end 18 of the connector 2 and is inclined forwardly along the length of the post 12 to the tip 17. The inclined, flat surface 19 merges with a bulbous, rounded end surface at the tip 17 of the post 12. An inward facing surface 20 of the post 12 is rounded and merges with the flat surface 19. The inward facing surfaces 20 of the posts 12 face each other. The ground receiving cavity 11 is a closed end channel in the rounded surface 20 that communicates with one of the ground contact receiving cavities in the housing 4. A ground contact 10 extends within the channel and along the rounded surface at the tip 17. The post 12 partially surrounds the portion of the ground contact 10 within the channel. With reference to Figures 4 and 5, the ground contacts 10 are stamped and formed from a blank of metal and are unitary with a carrier strip 15, Figure 4. Each ground contact 10 is separated from the carrier strip 15. An outwardly curved, contact surface 21 on the ground contact 10 projects outwardly of the channel to engage a ground contact 10 in the mating electrical connector 3, when the ground contacts 10 along the posts 12 are received along the channels of the mating connector 3 for connection with the ground contacts 10 in the channels of the mating connector 3. An insulating funnel 22 is on the open end of each of the ground contact receiving cavities 11 in the mating connector 3. The ground contact 11 in each of the cavities 11 is recessed from the open end. Because the ground contacts 10 of both connectors 2, 3 are positioned rearwardly, when the posts 12 are inserted along the cavities 11 of the mating connector 3, the open ends of the cavities 11 will be covered by the posts 12 before the ground contacts 10 of the connectors 2, 3 become engaged. Thereby, the ground contacts and the cavities 11 will be covered safely in the event that electrical arcing might occur when the ground contacts 10 of the connectors 2, 3 approach one another during mating connection. Prior to connecting the mating face 6 of the connector 2 with the mating electrical connector 3, the ground contacts 10 on the alignment posts 12 engage the ground contacts 10 in the mating electrical connector 3. Thus, the ground contacts 10 become engaged with the mating electrical connector 3 before the electrical contacts 7 become engaged with the mating electrical connector 3. The ground contacts 10 of the mating connector 3 are connected to chassis ground, electrical potential. When the ground contacts 10 of the connectors 2, 3 are engaged, the ground connections of the connector 2 to chassis ground potential is established before the contacts 7 of the connector 2 engage the contacts 7 of the mating connector 3. It can be said of the invention, that the subsequent contacts 7, combined with the prior connection of the longer ground contacts 10, provide at least two levels of sequenced electrical connections with the mating electrical connector 3. The contacts 7 are protected from electrostatic charges when the charges are discharged to chassis ground. In addition, the connection of the contacts 7 in the respective connectors 2, 3 can be accomplished when the contacts 7 of the mating connector 3 are part of an activated electrical circuit, not shown. A feature of the invention resides in electrical contacts 7 in the mating electrical connector 3 being engaged by the multiple electrical contacts 7 of the connector 2 subsequent to engagement of the ground contacts 10 of the respective connectors 2, 3. In other words, the ground contacts 10 of the connector 2 first engage the ground contacts 10 of the mating electrical connector 3, and subsequently, the contacts 7 of the connector 2 engage the contacts 7 of the mating electrical connector 3. This feature discharges electrostatic charges through the engaged ground contacts 10 to isolate the electrical contacts 7 from such charges during connection and disconnection of the connector 2 and the mating electrical connector 3. The contacts 7 of the connectors 2, 3 are capable of connection and disconnection from one another while the contacts 7 of one of the connectors 2, 3 is part of an activated electrical circuit, not shown. The connector 2 shown in Figure 1 is capable of being modified to provide a desirable feature wherein, mating connection of the electrical contacts 7 of the connectors 2, 3 will occur in sequence. Selected electrical contacts 7 in the connector 2 are positioned forward and closer to the mating face 6 than are the remainder of the electrical contacts 7 when the connector 2 of Figure 1 is being viewed from the mating face 6. As the connectors 2, 3 are moved toward each other for mating connection, the forward contacts 7 will engage respective contacts 7 of the other mating connector 3 before the remainder of the contacts 7 in the connector 2 become engaged with the remainder of the contacts 7 of the mating connector 3. This feature provides another level of sequenced electrical connection when the connectors 2, 3 are urged toward one another for mating connection. With reference to the connector 2 shown in Figure 2, the shroud 14 is divided into several spaced apart sections, and different types of contacts 7 are encircled by the respective sections of the shroud 6. Among the different types of contacts 7, the contacts 7 that are alike are positioned forward and closer to the mating face 6 than are the remainder of the contacts 7. The contacts 7 in at least one selected section of the shroud 14 are selected to be located forward of the remainder of the contacts 7 in the remaining sections of the shroud 6. This feature provides another level of sequenced electrical connection when the connectors 2, 3 are urged toward one another for mating connection.

Claims: An electrical connector assembly comprising first and second matable electrical connectors (2,3) having matable electrical contacts (7) secured therein for electrical connection when the electrical connectors are mated together, and ground contacts (10) for electrical connection when the connectors are mated together, characterized in that insulative alignment posts (12) and cavities (11) are provided on the matable connectors (2,3), and the ground contacts (10) extend along the alignment posts and cavities and, when the connectors are mated together, electrically engage each other before engagement of the electrical contacts (7). An electrical connector assembly as claimed in claim 1, wherein the alignment cavities (11) are disposed on one of the matable connectors (2,3) and the alignment posts (12) are disposed on the other. An electrical connector assembly as claimed in claim 1 or 2, wherein the alignment posts (12) are formed at opposite ends of one of the connectors (2,3) and the ground contacts (10) extend along the inside surfaces thereof.

Inventors: BIECHLER DONALD TIMOTHY, COSTELLO BRIAN PATRICK, MYERS JR EARL CHESTER, WALKER ROBERT WAYNE, WHITEMAN ROBERT NEIL, BIECHLER, DONALD TIMOTHY, COSTELLO, BRIAN PATRICK, MYERS JR., EARL CHESTER, WALKER, ROBERT WAYNE, WHITEMAN, ROBERT NEIL
Applicants: WHITAKER CORP, THE WHITAKER CORPORATION
Application year: 1994
Main classification: H01R13
IPC codes: H01R13, H01R24, H01R12